Results 1 to 4 of 4

Math Help - complex variables, determining shape?

  1. #1
    Junior Member
    Joined
    Nov 2009
    Posts
    73

    complex variables, determining shape?

    The question is to sketch the set of points determined by the equation.
    |3z - 2i|>= 4

    I know that if it was say |z -1 - 2i| = 2 that its a circle centered at (1,2) with radius 2. But im not sure how to interpret the above equation.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member craig's Avatar
    Joined
    Apr 2008
    Posts
    748
    Thanks
    1
    Awards
    1
    Try dividing by 3, should help you along
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Nov 2009
    Posts
    73
    okay so now I have that |z-2/3 i|>=4/3 so im interpretting this as center of the circle is at 2/3i and radius is 4/3 and since the inequality is >= i want everything outside of the circle. Does this make sense?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member craig's Avatar
    Joined
    Apr 2008
    Posts
    748
    Thanks
    1
    Awards
    1
    Quote Originally Posted by scubasteve123 View Post
    okay so now I have that |z-2/3 i|>=4/3 so im interpretting this as center of the circle is at 2/3i and radius is 4/3 and since the inequality is >= i want everything outside of the circle. Does this make sense?
    Yep that seems right from here.

    Just remember that as the inequality is \geq, you will need to include the line of the circle as well.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Determining a shape from length/slope
    Posted in the Algebra Forum
    Replies: 1
    Last Post: December 8th 2011, 04:27 AM
  2. Replies: 4
    Last Post: August 16th 2011, 05:01 AM
  3. Determining complex roots
    Posted in the Algebra Forum
    Replies: 2
    Last Post: November 2nd 2009, 07:21 AM
  4. Replies: 3
    Last Post: August 2nd 2009, 01:48 AM
  5. Replies: 5
    Last Post: March 3rd 2009, 09:33 AM

Search Tags


/mathhelpforum @mathhelpforum